Experts have known for years that coloring can be an effective form of therapy for kids. Unless, of course, you're asking them to color the very thing that traumatized them in the first place. For example, a giant intoxicated Easter bunny or a national tragedy.
Imagine you're a New Yorker sitting in a classroom 10 years after the World Trade Center attacks. To commemorate the anniversary, your teacher hands you a sheet that requires you to color the smoke billowing from the towers. Do you choose gray? Maybe a nice black-and-white mix with a little splash of cadet blue to add texture? The important thing is that you keep your strokes in the lines while remembering that under all those windows are thousands of trapped office workers and firefighters running for the exits before the buildings fall. It's tempting to give the publishers of this crime against taste the benefit of the doubt, as if their hearts were in the right place, even if they had the subtlety of a nuclear holocaust. The temptation to assume the best about the publisher is obliterated once you see the rest of the coloring book.